The 3rd Generation Partnership Project (3GPP), which is a standardization project, has standardized Evolved Universal Terrestrial Radio Access (EUTRA), in which high-speed communication is realized by adopting an Orthogonal Frequency-Division Multiplexing (OFDM) communication method and flexible scheduling in a unit of prescribed frequency and time called a resource block. EUTRA may also be referred to as Long Term Evolution (LTE).
Moreover, the 3GPP has been considering LTE Advanced (also referred to as LTE-A) which realizes higher-speed data transfer and has upper compatibility with LTE.
For LTE Advanced, a cost reduction (also referred to as low complexity) of a terminal device used for Machine Type Communication (MTC) or Machine To Machine Communication (M2M) has been considered (NPL 1). Hereinafter, a terminal device or a communication device designed for MTC/M2M and having the function capable of (supporting) a cost reduction and/or Coverage Enhancement is also referred to as Machine Type Communication User Equipment (MTCUE). However, the use of such a terminal device is not limited to Machine Type Communication nor Machine To Machine Communication.
The 3GPP has proposed, in order to realize low cost MTCUE, the narrowing of a transmission and reception bandwidth, a reduction of the number of antenna ports/the number of RF chains, a reduction of the transmission and reception data transfer rate, adoption of a Half-duplex Frequency Division Duplex scheme, a reduction of transmit and receive power, an extension of Discontinuous Reception intervals, and the like. Furthermore, the 3GPP has also proposed, as a method of realizing the low cost MTCUE, a reduction of the maximum bandwidth of a transmission and reception RF circuit and a transmission and reception baseband circuit of MTCUE, and the like.
Furthermore, in order to compensate for degradation in reception and transmission performance due to the influence of the reduction in the number of the antenna ports or the like, a method has been considered in which downlink data or a downlink signal is repetitively transmitted to MTCUE for one data transmission, and MTCUE repetitively transmits uplink data or an uplink signal to a base station device for one data transmission.
Additionally, not only cost reduction, but also Coverage Enhancement (Coverage Improvement), coverage being a transmission and reception range of MTCUE, has been considered. For example, with respect to spaces such as basements which are outside the communication area due to a large signal attenuation in the related art, the Coverage Enhancement has been considered. In order to enhance the coverage, a method has been considered in which the base station device repetitively transmits downlink data or a downlink signal to MTCUE, and MTCUE repetitively transmits uplink data or an uplink signal to the base station device (NPL 2).
For example, the base station device repetitively transmits a Physical Broadcast Channel PBCH to MTCUE multiple times within 40 ms. Furthermore, in a random access procedure, MTCUE repetitively transmits the same random access preamble with multiple resources of a Physical Random Access Channel PRACH. The base station device which has received the random access preamble repetitively transmits a random access response message. Note that, the base station device notifies MTCUE in a cell of the number of repetitions (the number of attempts) with system information, or dedicatedly notifies MTCUE (NPL 2).